Imaging G-Ratio in Multiple Sclerosis Using High-Gradient Diffusion MRI and Macromolecular Tissue Volume

BACKGROUND AND PURPOSE

Remyelination represents an area of great therapeutic interest in multiple sclerosis but currently lacks a robust imaging marker. The purpose of this study was to use high-gradient diffusion MRI and macromolecular tissue volume imaging to obtain estimates of axonal volume fraction, myelin volume fraction, and the imaging g-ratio in patients with MS and healthy controls and to explore their relationship to neurologic disability in MS.

MATERIALS AND METHODS

Thirty individuals with MS (23 relapsing-remitting MS, 7 progressive MS) and 19 age-matched healthy controls were scanned on a 3T MRI scanner equipped with 300 mT/m maximum gradient strength using a comprehensive multishell diffusion MRI protocol. Macromolecular tissue volume imaging was performed to quantify the myelin volume fraction. Diffusion data were fitted to a 3-compartment model of white matter using a spheric mean approach to yield estimates of axonal volume fraction. The imaging g-ratio was calculated from the ratio of myelin volume fraction and axonal volume fraction. Imaging metrics were compared between groups using 2-sided t tests with a Bonferroni correction.

RESULTS

The mean g-ratio was significantly elevated in lesions compared with normal-appearing WM (0.74 vs 0.67, P < .001). Axonal volume fraction (0.17 vs 0.23, P < .001) and myelin volume fraction (0.17 vs 0.25, P < .001) were significantly lower in lesions than normal-appearing WM. Myelin volume fraction was lower in normal-appearing WM compared with that in healthy controls (0.25 vs 0.27, P = .009). Disability, as measured by the Expanded Disability Status Scale, was significantly associated with myelin volume fraction (β = -40.5, P = .001) and axonal volume fraction (β = -41.0, P = .016) in normal-appearing WM.

CONCLUSIONS

The imaging g-ratio may serve as a biomarker for the relative degree of axonal and myelin loss in MS.

Temperature field model and control strategy in gravity casting process

Temperature control is one of the most important processes during aluminum (Al) alloy engine cylinder head product casting. An improper temperature control may result in no uniformity and microstructure defects in casting parts and give rise to high defect ratio. In this paper, a mathematical model with high nonlinearity, strong coupling, and less uncertainty is developed for the solidification process in Al alloy casting. The interfacial heat transfer coefficient is combined with the mold structure comprehensively to build the temperature-structure model, and the characteristics of the uncertainty conversion are also used in order to achieve optimal temperature control during the solidification process. The cloud model integrated with Proportion-Integral-Differential (PID) temperature control system enables evaluation of the uncertainty conversion quantitatively. By inputting the temperature error and the temperature error rate, the PID inference is output through the cloud inference engine to achieve the optimal temperature curve. The superiority of the control algorithm was verified on a customized experimental platform with the temperature control system. Compared with manual operation and traditional PID control, the result shows that the error of the cloud model control is lower than the manual operation and traditional PID control. The experimental results also suggest that the performance of our cloud model is better than that of the manual operation model and the traditional PID control model regarding to stability and controllability.

Altered Fractional Amplitude of Low Frequency Fluctuations in Unmedicated Female Patients with Obsessive-Compulsive Disorder

A number of resting-state functional magnetic resonance imaging (rs-fMRI) studies indicate dysfunction of large-scale brain networks underlying the pathophysiology of obsessive-compulsive disorder (OCD). Recent epidemiology studies show that the prevalence of female OCD patients is higher than that of males. However, the underlying neurobiology mechanism for female OCD patients remains not fully understood. In this study, we are aimed to explore the spontaneous brain neuronal activity in unmedicated female OCD patients using rs-fMRI methodology and fractional amplitude of low frequency fluctuations (fALFF) analysis. Additionally, we examine the relationship between fALFF changes and female OCD symptomatology. Increased fALFF values in right brainstem, right rectus, left middle temporal gyrus and right angular were found in OCD females. And decreased fALFF values in right cerebellum, left middle occipital gyrus, left insula, postcentral gyrus and left precentral gyrus were shown in female OCD patients. Moreover, the fALFF values in left precentral gyrus and left middle temporal gyrus were positively associated with patients YBOCS-Obsessions scores and HAMD scores, respectively. Our findings bring additional insights in understanding the pathophysiology of female OCD patients.

P1216Evaluation of alphavbeta3 integrin-targeted positron emission tomography and photoacoustic tracer for imaging of carotid plaque in apoE–/– mice

Background

Cardiovascular disease is the leading cause of death in the world. The majority of cardiovascular events result from the rupture of vulnerable atherosclerotic plaques, which are characterized by high and active macrophage content. The integrin αVβ3 is expressed by activated macrophages and endothelial cells in atherosclerotic lesions and thus is a marker of high-risk plaques. Therefore, 89Zr-RGD-melanin nanoparticle (MNP) positron emission tomography (PET)/photoacoustic imaging (PAI) imaging of αVβ3 expression in plaques might provide a novel noninvasive biomarker of plaque vulnerability.

Purpose

In this study, the intrinsic photoacoustic signals and the native strong chelating properties with metal ions of MNP, positron-emitting metal ions 89Zr and αVβ3 integrins targeting ability of cyclic c (RGDfC) peptide was employed to construct an efficient nanoplatform. And we evaluated the feasibility of 89Zr-RGD-MNP PET/PAI of αVβ3 expression in vivo and in vitro.

Methods

We conjugated αVβ3 integrins, cyclic c (RGDfC) peptide, to MNP and chelated the long-lived positron-emitting nuclide 89Zr. The bio-stability and targeting action was detected in macrophages. And the PET/PAI imaging was performed in apoE−/− mice with partial carotid ligation leading to atherosclerosis. In PET imaging, tracer uptake was measured in the stenotic areas of the carotid arteries, as well as on the contralateral side at different time points in vivo. In PAI, photoacoustic signal was measured in the atherosclerosis of the carotid arteries in vivo. Melanin staining and immunohistochemistry of αVβ3 expression were detected in atherosclerosis of the carotid arteries.

Results

89Zr-RGD-MNP showed excellent bio-stability and targeting action. PET imaging showed specific tracer accumulation at plaques in the left carotid artery, confirmed by competitive receptor blocking studies and the contrast in the right carotid artery. In the biodistribution studies, the left carotid (5.29%±0.78%) showed higher uptake than the right carotid (2.11%±1.55%). PAI showed the PA signal in the surgery group (452±85 a.u.) were stronger than the control (156±45 a.u.) and blocking group (254±66 a.u). The result was consistent with PET imaging and the presence of nanoparticles, as indicated by pathological examinations. These results presented good in vivo multimodality imaging (PET/PAI) properties.

Conclusions

We have developed 89Zr-labeled atherosclerotic plaques imaging agents based on the natural melanin nanoparticle. 89Zr-RGD-MNP demonstrates specific tracer accumulation in mice atherosclerotic carotid plaques. In this model, its uptake was associated with αVβ3 expression. 89Zr-RGD-MNP is a potential tracer for noninvasive imaging in atherosclerosis.

Acknowledgement/Funding

National Natural Science Foundation of China 81770452, 81470401

Levels of fractional exhaled nitric oxide in children in relation to air pollution in Chinese day care centres

OBJECTIVE

To study fractional exhaled nitric oxide (FeNO) levels among pre-school children in day care centres (DCCs) in relation to indoor and outdoor air pollution in northern China.

DESIGN

This was a cross-sectional study among children aged 5 years from 34 classrooms at 10 randomly selected DCCs in Taiyuan, China. A total of 507 (99%) children participated. Air pollution and carbon dioxide (CO2) levels were measured in the classroom and outside the school. Linear mixed models were applied for statistical analysis.

RESULTS

The geometric mean FeNO was 9.1 ± 1.5 parts per billion; 11.6% of children had wheeze, 6.0% had dry cough, 26.4% rhinitis symptoms, 1.6% ever physician-diagnosed asthma and 29.2% ever physician-diagnosed pneumonia. FeNO levels were associated with current wheeze (P = 0.04) and ever physician-diagnosed pneumonia (P = 0.05). The mean indoor concentrations were particulate matter with a diameter of <2.5 μm (PM2.5) 268 μg/m3, sulfur dioxide (SO2) 40.5 μg/m3, nitrogen dioxide (NO2) 43.0 μg/m3 and CO2 827 parts per million. Outdoor concentrations were PM2.5 244 μg/m3, SO2 106.6 μg/m3 and NO2 40.9 μg/m3. PM2.5 levels inside (P = 0.002) and outside DCCs (P = 0.05) were associated with FeNO levels.

CONCLUSION

PM2.5 levels inside and outside DCCs in China can contribute to airway inflammation in pre-school children. Children with current wheeze and ever physician-diagnosed pneumonia may have higher FeNO levels.

Optimization of Dietary Zinc Requirement for Broiler Breeder Hens of Chinese Yellow-Feathered Chicken

Simple Summary

China is the second-largest global producer of chicken meat, almost half of which is from the Chinese yellow-feathered breed; a systematic program has been initiated to improve its feeding standards. This study evaluated the optimal requirement of dietary zinc for maximal egg production, egg quality, tibial quality, and antioxidant indices of laying broiler breeders. The results revealed several beneficial effects of supplementary zinc on egg production, feed conversion ratio, yolk zinc content, tibial quality and the antioxidant indices in the serum, liver and ovary. The optimal zinc requirement was estimated based on a regression model.

Abstract

This study aimed to establish the optimal dietary zinc requirement of Chinese yellow-feathered Lingnan broiler breeders. A total of 576 breeder hens aged 58 weeks were randomly assigned to six treatments, each with 6 replicates of 16 birds (n = 96/treatment). The hens were fed either a basal diet (22.81 mg/kg Zn) or the same basal diet supplemented with additional 24, 48, 72, 96, and 120 mg Zn/kg up to 65 weeks of age. Compared to the results of birds fed the basal diet (22.81 mg Zn/kg), the dietary supplementation with additional Zn (mg/kg) showed higher egg laying rate (at 48–120 mg), EM (at 96 mg/kg), yolk Zn content (at 24–120 mg/kg), fertility (at 48–120 mg/kg), hatchability (at 48–96 mg/kg), tibial breaking strength (at 24–48 mg/kg), tibial ash content (at 48 mg/kg), serum CuZnSOD activity (at 72 mg/kg) and T-AOC (at 48 mg/kg), and ovarian CuZnSOD and GSH-Px activities (at 96–120 mg/kg), and lower FCR (at 96 mg/kg). The regression model showed that the optimal supplemental Zn for maximal egg laying rate, yolk Zn content, fertility, and hatchability of Chinese yellow-feathered broiler breeders aged 58 to 65 weeks were 71.09, 92.34, 94.44 and 98.65 mg/kg diet, respectively.

Impacts of Graded Levels of Metabolizable Energy on Growth Performance and Carcass Characteristics of Slow-Growing Yellow-Feathered Male Chickens

A dose-response study was conducted to investigate the metabolizable energy (ME) requirement for Lingnan chickens from 9 to 15 weeks of age. One thousand two hundred 8-week-old slow-growing yellow-feathered male chickens were allotted to five dietary ME levels (2805, 2897, 2997, 3095 and 3236 kcal/kg). The results revealed that the daily metabolizable energy intake increased (p < 0.01), whereas the feed intake and feed:gain ratio decreased linearly (p < 0.01) with the increment in dietary ME level. The final body weight and daily gain of the highest ME treatment tended (p > 0.05) to be greater than those obtained with the lower ME levels. The fat content in breast muscle showed a quadratic response (p < 0.05) to the increase in dietary energy level. The shear force values of breast muscle in the 2897, 3095 and 3236 kcal/kg treatments were lower (p < 0.05) than those of the 2997 kcal/kg treatment. In conclusion, among the tested ME levels, 3095 kcal/kg was adequate for feed intake, shear force, and plasma uric acid, and 3236 kcal/kg tended to increase the body weight, body gain, and feed conversion ratio of Lingnan males between 9 and 15 weeks of age; further studies are still required for testing higher levels.

[Epidemiological characteristics of molecular transmission cluster among reported HIV/AIDS cases in Jiaxing city, Zhejiang province, 2017]

Objective: To understand the epidemiological characteristics of one large HIV molecular transmission cluster in Jiaxing city, Zhejiang province, 2017 in order to select those people under high-risk and providing basis for programs on prevention. Methods: During 2017, newly diagnosed HIV/AIDS cases in this city were recruited. Plasma samples were collected from subjects, followed by RNA extraction, RT-PCR and nest-PCR for pol gene amplification, before being sequenced and aligned. Mega 6.0 software was used to construct phylogenetic tree, and Cytoscape 3.6.0 software was used to identify HIV molecular transmission clusters. Cases within the large transmission clusters were investigated, using a field-epidemiology-questionnaire. Data related to socio-demographics and previous sexual behaviors were collected and EpiData 3.0 and SPSS 20.0 software were used. Results: In the large transmission cluster with subtype identified as CRF07_BC, in Jiaxing, 2017, 26 cases of the total 30 cases were investigated. A total of 80.8% (21/26) could be identified as newly infected within the last two years and 30.8%(8/26) could be identified as newly infected within the last one year, including 22 cases infected locally. Among several infected cases who were at age 45 years or older, they admitted that they had experienced unprotected sexual contacts in local city for long time and having had more than 10 disclosed sexual contacts within the last two years at the local venues. Conclusions: This molecular cluster had been formed and scaled up quickly in recent two years, it has played an important role in promoting and scaling up the HIV transmission. Three cases identificed as high risk played an importantrde role in scaling up this cluster.

Infection with sodA mutant of S. Typhimurium leads to up-regulation of autophagy in Raw264·7 macrophages

Salmonella enterica serovar Typhimurium (S. Typhimurium) inhabits a wide range of hosts, including poultry, and causes acute gastroenteritis in humans that may result in death. Superoxide dismutase (SOD) is an important antioxidant enzyme present in nearly all living cells exposed to oxygen. Recently, we reported the novel roles of SOD in serum resistance and biofilm formation in S. Typhimurium. This study was designed to explore the effect of infection with sodA mutant of S. Typhimurium on the autophagic response of macrophages. Murine macrophage cell line RAW264·7 was infected with wild-type (LSM52), a sodA deletion mutant (LSM52ΔsodA) and complemented strain (LSM52CΔsodA). We found that sodA deletion triggered remarkable autophagic responses in infected cells, shown as higher concentrations of LC3-II or Beclin-1 than those infected with the wild-type or complemented strain during the first hour post-infection in S. Typhimurium. Consistent with these results, the number of viable bacteria in cells infected with the sodA mutant was significantly lower than those infected with wild-type or complemented strains at 1 h, 2 h and 3 h post-infection in S. Typhimurium. All results indicated that infection with sodA mutant of S. Typhimurium leads to up-regulation of autophagy in Raw264·7 macrophages. SIGNIFICANCE AND IMPACT OF THE STUDY: Autophagy plays an important role in Salmonella infection although the role of autophagy in Salmonella infection remains unclear. This study was designed to explore the effect of sodA on the autophagic response of macrophage. We found that infection with sodA mutant of Salmonella Typhimurium could lead to up-regulation of autophagy in Raw264·7 macrophages.

Hierarchical measurement structure in the Women's Health Questionnaire: a confirmatory factor analysis

Purpose: This study conducted confirmatory factor analysis (CFA) to examine the measurement structure of the Women's Health Questionnaire (WHQ) and how its components were organized. Methods: Participants were 448 postmenopausal women, with a mean age of 63.3 years. CFA was conducted to test how well several proposed measurement models fit the data. Results: The single-factor model performed poorly, indicating the presence of multiple factors. The model with seven correlated factors fit the data well, although the varying degrees of inter-factor correlations suggested grouping of similar factors. The hierarchical measurement structure, with seven first-order factors organized under two second-order factors of physical health and mental health functioning, demonstrated a good fit with the data (χ²(367) = 694.05, p < 0.001; root mean square error of approximation = 0.05; comparative fit index = 0.95) and a meaningful pattern. The Mental Health factor was represented by Depressed Mood, Anxiety/Fear, Memory/Concentration Problems, and Sleep Problems. The Physical Health factor was manifested mainly by Somatic Symptoms, Menstrual Symptoms, and Vasomotor Symptoms, and, to a lesser extent, also by Sleep Problems and Memory/Concentration Problems. Conclusion: Findings suggested that, in addition to a global index and subscale scores, the WHQ may produce summary scores of physical health and mental health functioning in evaluation of well-being among postmenopausal women.

MicroRNA-182 suppresses clear cell renal cell carcinoma migration and invasion by targeting IGF1R

The purpose of our study was aimed to determine the functional role of microRNA (miR)-182 in clear cell renal cell carcinoma (ccRCC) and try to clarify its underlying molecular mechanism. Expression of miR-182 in both cancer and peripheral blood samples was analyzed by quantitative real-time PCR (qRT-PCR). Human RCC line Caki-1 cells were transfected with miR-182 mimic, miR-182 inhibitor, or negative controls, and then the cell viability, colony-formation ability, migration, and invasion assay were determined. Luciferase reporter assay, qRT-PCR and Western blotting were used to determine whether insulin-like growth factor 1 receptor (IGF1R) was a target of miR-182. Further, small interfering RNA (siRNA) against IGF1R was co-transfected with miR-182 inhibitor into cells, and then the effects on migration and invasion were assessed. MiR-182 was down-regulated in both cancer and blood samples compared to the matched non-tumor adjacent tissues and healthy volunteers, respectively (both P<0.05). Compared to the control group, cell viability, colony-forming ability, and numbers of migrated and invaded cells were significantly decreased by transfection with miR-182 mimic but were markedly increased by miR-182 inhibitor (all P < 0.05). Luciferase reporter assay confirmed that IGF1R was a target gene of miR-182, and IGF1R was negatively regulated by miR-182. Co-transfection of miR-182 inhibitor with si-IGF1R reversed the effect of miR-182 inhibitor on the migration and invasion of the cells. MiR-182 functions as an anti-oncogene in ccRCC, and miR-182-mediated inhibition of cell migration and invasion might be through directly targeting IGF1R.

Asthma symptoms among Chinese children: the role of ventilation and PM10 exposure at school and home

SETTING

Respiratory symptoms in relation to environment in Taiyuan, China.

OBJECTIVE

To study associations between school/home exposure and prevalence of respiratory symptoms and self-reported respiratory infections (RIs) among students.

DESIGN

A total of 2134 pupils from 10 schools answered a questionnaire; air pollution at school was measured.

RESULTS

The prevalence of current wheeze, daytime attacks of breathlessness, nocturnal cough, nocturnal respiratory symptoms and RI was respectively 4.4%, 18.7%, 11.6%, 3.6% and 32.3%. Environmental tobacco smoke (ETS) at home was associated with daytime attacks of breathlessness (OR 1.41), nocturnal cough (OR 1.41) and RI (OR 1.26). Redecoration or indoor painting at home was associated with wheeze (OR 2.02), daytime attacks of breathlessness (OR 1.57) and nocturnal symptoms (OR 1.83). Dampness or mould at home was associated with daytime attacks of breathlessness (OR 1.68), nocturnal cough (OR 1.68) and RI (OR 1.69). Particulate matter of diameter  10 microns (PM10) in the classroom was associated with nocturnal cough (OR 1.20/10 μg/m3). PM10 outside school was associated with daytime attacks of breathlessness (OR 1.07/10 μg/m3) and nocturnal cough (OR 1.13/10 μg/m3). Indoor carbon dioxide, a marker of poor ventilation (OR 1.52/1000 parts per million), and relative humidity (RH) (OR 1.33/10%) were associated with nocturnal cough.

CONCLUSION

Dampness, redecoration and ETS at home, as well as poor ventilation flow, and high RH and PM10 concentration at school may influence respiratory health.

Use of integrative epigenetic and mRNA expression analyses to identify significantly changed genes and functional pathways in osteoarthritic cartilage

Aim

Osteoarthritis (OA) is caused by complex interactions between genetic and environmental factors. Epigenetic mechanisms control the expression of genes and are likely to regulate the OA transcriptome. We performed integrative genomic analyses to define methylation-gene expression relationships in osteoarthritic cartilage.

Patients and Methods

Genome-wide DNA methylation profiling of articular cartilage from five patients with OA of the knee and five healthy controls was conducted using the Illumina Infinium HumanMethylation450 BeadChip (Illumina, San Diego, California). Other independent genome-wide mRNA expression profiles of articular cartilage from three patients with OA and three healthy controls were obtained from the Gene Expression Omnibus (GEO) database. Integrative pathway enrichment analysis of DNA methylation and mRNA expression profiles was performed using integrated analysis of cross-platform microarray and pathway software. Gene ontology (GO) analysis was conducted using the Database for Annotation, Visualization and Integrated Discovery (DAVID).

Results

We identified 1265 differentially methylated genes, of which 145 are associated with significant changes in gene expression, such as DLX5, NCOR2 and AXIN2 (all p-values of both DNA methylation and mRNA expression < 0.05). Pathway enrichment analysis identified 26 OA-associated pathways, such as mitogen-activated protein kinase (MAPK) signalling pathway (p = 6.25 × 10-4), phosphatidylinositol (PI) signalling system (p = 4.38 × 10-3), hypoxia-inducible factor 1 (HIF-1) signalling pathway (p = 8.63 × 10-3 pantothenate and coenzyme A (CoA) biosynthesis (p = 0.017), ErbB signalling pathway (p = 0.024), inositol phosphate (IP) metabolism (p = 0.025), and calcium signalling pathway (p = 0.032).

Conclusion

We identified a group of genes and biological pathwayswhich were significantly different in both DNA methylation and mRNA expression profiles between patients with OA and controls. These results may provide new clues for clarifying the mechanisms involved in the development of OA.

Cite this article: A. He, Y. Ning, Y. Wen, Y. Cai, K. Xu, Y. Cai, J. Han, L. Liu, Y. Du, X. Liang, P. Li, Q. Fan, J. Hao, X. Wang, X. Guo, T. Ma, F. Zhang. Use of integrative epigenetic and mRNA expression analyses to identify significantly changed genes and functional pathways in osteoarthritic cartilage. Bone Joint Res 2018;7:343–350. DOI: 10.1302/2046-3758.75.BJR-2017-0284.R1.

A novel near-infrared nanomaterial with high quantum efficiency and its applications in real time in vivo imaging

Fluorescence imaging signal is severely limited by the quantum efficiency and emission wavelength. To overcome these challenges, novel NIR-emitting K₅NdLi₂F₁₀ nanoparticles under NIR excitation was introduced as fluorescence imaging probe for the first time. The photostability of K₅NdLi₂F₁₀ nanoparticles in the water, phosphate buffer saline, fetal bovine serum and living mice was investigated. The fluorescence signal was detected with depths of 3.5 and 2.0 cm in phantom and pork tissue, respectively. Fluorescence spectrum with a significant signal-to-background ratio of 10:1 was captured in living mice. Moreover, clear NIR images were virtualized for the living mice after intravenous injection. The imaging ability of nanoparticles in tumor-beard mice were evaluated, the enrichment of K₅NdLi₂F₁₀ nanoparticles in tumor site due to the enhanced permeability and retention effect was confirmed. The systematic studies of toxicity, bio-distribution and in-vivo dynamic imaging suggest that these materials give high biocompatibility and low toxicity. These NIR-emitting nanoparticles with high quantum efficiency, high penetration and low toxicity might facilitate tumor identification in deep tissues more sensitively.

An Optimal Enhanced Kalman Filter for a ZUPT-Aided Pedestrian Positioning Coupling Model

Aimed at overcoming the problems of cumulative errors and low positioning accuracy in single Inertial Navigation Systems (INS), an Optimal Enhanced Kalman Filter (OEKF) is proposed in this paper to achieve accurate positioning of pedestrians within an enclosed environment. Firstly, the errors of the inertial sensors are analyzed, modeled, and reconstructed. Secondly, the cumulative errors in attitude and velocity are corrected using the attitude fusion filtering algorithm and Zero Velocity Update algorithm (ZUPT), respectively. Then, the OEKF algorithm is described in detail. Finally, a pedestrian indoor positioning experimental platform is established to verify the performance of the proposed positioning system. Experimental results show that the accuracy of the pedestrian indoor positioning system can reach 0.243 m, giving it a high practical value.

[Analysis on HIV-1 subtypes and transmission clusters in newly reported HIV/AIDS cases in Yiwu, Zhejiang Province, 2016]

Objective: To understand the characteristics of distribution on HIV-1 subtypes and the transmission clusters in Yiwu in Zhejiang province. Methods: A cross-sectional study of molecular epidemiology was carried out on newly reported HIV/AIDS cases in Yiwu. RNA was extracted from 168 plasma samples, followed by RT-PCR and nest-PCR for pol gene amplification, sequencing, phylogenetic tree construction used for analyzing the subtypes and transmission clusters. Mutations on drug resistance was analyzed by CPR 6.0 online tool. Results: Subjects were mainly males (86.3%, 145/168), with average age as (39.1±13.4) years old and most of them were migrants (66.7%, 112/168). The major routes of transmission included homosexual (51.2%, 86/168) and heterosexual (48.8%, 82/168) contacts. The rate of success for sequence acquisition was 89.9% (151/168). The dominant subtypes showed as CRF01_AE (74, 49.0%) and CRF07_BC (64, 42.4%), followed by CRF08_BC (5, 3.3%), CRF55_01B (3, 2.0%), each case of subtype B, CRF45_cpx, CRF59_01B, CRF85_BC and URF (B/C). CRF45_cpx and CRF85_BC were discovered the first time in Zhejiang province. Twenty-six transmission clusters involving 65 cases were found, with the total clustered rate as 43.0% (65/151), in which the CRF01_AE clustered rate appeared as 54.1% (40/74), higher than that of CRF07_BC (21/64, 32.8%). The average size of cluster was 2.5 cases/cluster, with average size of cluster in CRF01_AE patients infected through heterosexual transmission as the largest (3.5 cases/cluster). The prevalence of transmitted drug resistance was 4.6% (7/151). Seven cases with surveillance drug resistant mutations (SDRM) were found, including 5 cases of M46L (3.3%), and one case of F77L or Y181C. Conclusion: HIV genetic diversity and a variety of transmission clusters had been noticed in this study area (Yiwu). Programs on monitoring the subtypes and transmission clusters should be continued and strengthened.

Genome-wide DNA methylation profiling of articular cartilage reveals significant epigenetic alterations in Kashin-Beck disease and osteoarthritis

OBJECTIVE

To determine genome-wide DNA methylation profiles of knee cartilage from patients with Kashin-Beck disease (KBD) and osteoarthritis (OA).

METHOD

Knee cartilage was collected from 14 grade III KBD patients, 5 primary OA patients and 13 healthy subjects. The genome-wide methylation profiles of 5 KBD cartilage, 5 OA cartilage and 5 normal cartilage were determined by Illumina HumanMethylation450 array. Illumina Methylation Analyzer package was employed for identifying differentially methylated CpG sites. Functional annotation and enrichment analysis of differentially methylated genes (DMG) were conducted using GeneRIF database, Ingenuity Pathway Analysis (IPA) and The Database for Annotation, Visualization and Integrated Discovery (DAVID). Mass spectrometry (MS) and immunohistochemistry (IHC) were conducted to validate the functional relevance of identified KBD associated gene.

RESULTS

We identified a total of 1212 differentially methylated CpG sites in KBD vs Normal, annotated to 264 hypermethylated and 368 hypomethylated genes. Comparing the DNA methylation profiles of KBD vs Normal and OA vs Normal detected overlap of 367 differentially methylated CpG sites (annotated to 182 genes) as well as 845 KBD-specific differentially methylated CpG sites (annotated to 471 unique genes). MS and IHC confirmed the hypermethylation status and decreased protein expression of HAPLN1 gene in KBD cartilage.

CONCLUSION

Our data implicate epigenetic dysregulation of a host of genes in KBD and OA. Furthermore, we observed common causal epigenetic changes shared by KBD and OA.

Integrative analysis of GWAS, eQTLs and meQTLs data suggests that multiple gene sets are associated with bone mineral density

Objectives

Several genome-wide association studies (GWAS) of bone mineral density (BMD) have successfully identified multiple susceptibility genes, yet isolated susceptibility genes are often difficult to interpret biologically. The aim of this study was to unravel the genetic background of BMD at pathway level, by integrating BMD GWAS data with genome-wide expression quantitative trait loci (eQTLs) and methylation quantitative trait loci (meQTLs) data

Method

We employed the GWAS datasets of BMD from the Genetic Factors for Osteoporosis Consortium (GEFOS), analysing patients’ BMD. The areas studied included 32 735 femoral necks, 28 498 lumbar spines, and 8143 forearms. Genome-wide eQTLs (containing 923 021 eQTLs) and meQTLs (containing 683 152 unique methylation sites with local meQTLs) data sets were collected from recently published studies. Gene scores were first calculated by summary data-based Mendelian randomisation (SMR) software and meQTL-aligned GWAS results. Gene set enrichment analysis (GSEA) was then applied to identify BMD-associated gene sets with a predefined significance level of 0.05.

Results

We identified multiple gene sets associated with BMD in one or more regions, including relevant known biological gene sets such as the Reactome Circadian Clock (GSEA p-value = 1.0 × 10^-4 for LS and 2.7 × 10^-2 for femoral necks BMD in eQTLs-based GSEA) and insulin-like growth factor receptor binding (GSEA p-value = 5.0 × 10^-4 for femoral necks and 2.6 × 10^-2 for lumbar spines BMD in meQTLs-based GSEA).

Conclusion

Our results provided novel clues for subsequent functional analysis of bone metabolism, and illustrated the benefit of integrating eQTLs and meQTLs data into pathway association analysis for genetic studies of complex human diseases.

Cite this article: W. Wang, S. Huang, W. Hou, Y. Liu, Q. Fan, A. He, Y. Wen, J. Hao, X. Guo, F. Zhang. Integrative analysis of GWAS, eQTLs and meQTLs data suggests that multiple gene sets are associated with bone mineral density. Bone Joint Res 2017;6:572–576.